On Aug 17, 12:17*pm, "Sue" wrote:

I've got 2 or 3, thought it might be the dogs but no previous
problems there. *On investigating it is ants.

Sometimes brown patches in lawns could be caused by chafer grubs.
http://www.bbc.co.uk/gardening/advic...s/identifier.s...

Or, indeed, leatherjackets. But normally the woodpeckers & friends
sort that out for me. I've seen the ants in my case.